This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The objective of the experiment is to screen crystals of type IV prepilin peptidase (TFPP), an integral membrane protein responsible for the cleavage of type IV prepilins in bacteria. TFPP has 8 transmembrane helices. It generated only small-size crystals (<10[unreadable]m thickness) and showed low-resolution diffraction at NSLS X29. We wanted to test these crystals at a higher intensity beamline equipped with a microdiffractometer. We were able to take full advantage of the features of 24-ID-E beamline and have obtained some diffraction images with improved resolution (although still insufficient to allow structural determination). Based on the information we obtained from the trip, we are in the process of making further improvement of crystallization conditions.